The  Johnson  Heat  Regulating-  Apparatus  is  fully  covered  by  letters  patent  in  the 

United  States  and  in  F oreign  Countries. 


Cl&wts 

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32  Si 
Mll3 

i Qon 


THE  JOHNSON 

System  of  Heat  Regulation  in  Schools. 

DEFECTS  IN  HEATING  APPARATUS. 

The  inventor  of  this  system  of  temperature  regulation  was  for  many  years  connected  with  institutions  of 
learning,  and  having  been  a large  part  of  the  time  in  the  department  of  Natural  Sciences,  was  in  a position  to 
be  well  informed  regarding  the  systems  of  heating  used  in  buildings  designed  for  school  purposes.  From 
his  observations  of  the  great  inconveniences,  discomforts,  and  unhealthfulness  of  the  variable  and  unequal  tem- 
peratures to  which  the  occupants  are  subjected,  his  attention  was  called  to  some  method  by  which  the  tempera- 
ture and  ventilation  of  school  buildings  might  be  kept  at  a proper  degree,  automatically,  thus  securing  a proper 
degree  of  heat  and  ventilation,  and  also  relieving  the  instructors  of  the  attention  which  an  attempt  at  regulation 
necessarily  requires.  In  no  other  buildings  are  the  defects  of  heating  and  ventilating  so  pernicious  as  in  school  build- 
ings, for  the  reason  that  in  no  other  buildings  are  the  rooms  so  constantly  occupied  by  a large  number  of  people  for 
such  long  periods  of  time.  In  private  buildings  the  number  of  occupants  per  room  is  so  small,  that,  although 
poorly  ventilated,  there  is  usually  a comparatively  large  amount  of  breathing  room  for  each  individual.  In 
churches  and  halls,  while  the  auditoriums  are  overcrowded  during  the  sessions,  yet  such  buildings  are  seldom 
occupied  upwards  of  two  hours  at  a time,  and  the  same  people  do  not,  day  after  day,  congregate  in  the  same 
places.  The  effects,  therefore,  are  not  as  marked,  as  the  people  in  attendance  are  only  subject  to  the  unhealth- 
ful conditions  for  a short  period  of  time  and  at  remote  intervals.  In  schools,  however,  the  case  is  entirely  dif- 
ferent; for  six  hours  in  a day,  and  for  five  days  in  the  week,  the  same  individuals  are  subjected  to  the  same 
abnormal  atmospheric  conditions,  and  what  makes  the  matter  still  worse  is  that  the  pupils  are  in  a state  of 
growth  and  development,  and  are  therefore  much  more  sensitive  in  their  organisms,  and  more  liable  to  be 
affected  by  the  variableness  of  the  temperature  and  the  unwholesomeness  of  the  air  which  they  breathe.  Since 
stoves  have  gone  out  of  use  in  school  buildings,  there  has  been  a gradual  improvement  in  the  matter  of  ventila- 
tion of  such  buildings,  especially  in  the  larger  towns  and  cities.  A stove  in  a school  room  is  absolutely  the 
worst  form  of  heating  which  could  be  devised  for  an  apartment  which  is  to  be  occupied  by  a body  of  children. 
It  simply  furnishes  heat  (and  often  overheat),  but  does  not  give  any  possible  change  of  atmosphere  of  the  room. 
The  only  means  of  obtaining  a change  of  air  is  by  opening  the  windows,  and  this  is  seldom  done  by  teachers, 
excepting  to  get  rid  of  the  surplus  heat,  rather  than  in  view  of  proper  ventilation.  As  a remedy  for  poor  ventila- 
tion, the  opening  of  the  windows  is  almost  as  bad  as  the  disease,  and  it  subjects  the  occupants  of  the  room  to 
drafts  of  air  and  certain  variations  of  temperature  which  are  almost  sure  to  result  in  catarrhs.  The  introduction 
of  what  is  called  the  hot  air  furnace,  placed  in  the  basement  of  school  buildings,  marked  a long  advance  in  the 
methods  of  heating  school-rooms,  for  the  reason  that  there  must  be  some  degree  of  ventilation  in  order  to  warm 
the  room,  as  it  is  well  known  that  no  warm  air  can  enter  the  room  unless  there  is  some  escape  for  the  foul  air, 
for  which  provision  must  be  made.  This  method  of  heating,  however,  does  not  have  the  effect  to  give  the  proper 
temperature,  for  as  one  furnace  usually  supplies  the  heat  to  several  apartments,  either  one  or  more  of  the  apart- 
ments is  liable  to  be  overheated,  in  order  to  properly  heat  some  other.  When  a room  is  overheated,  the  teacher 
has  recourse  to  either  open  the  window  or  close  the  register,  at  the  same  time  exercising  his  discretion  in  per- 
forming both  operations,  thus  shutting  off  the  ingress  of  pure  warm  air  and  retarding  ventilation.  It  is  evident 


from  this  mode  of  controlling  ventilation,  that  even  a hot  air  furnace  will  not  supply  proper  ventilation  and 
heating.  Where  steam  furnaces  are  used  for  heating  school  buildings,  they  may  be  as  bad  as  stoves  or  as 
good  as  a hot  air  furnace,  depending  upon  the  system  adopted.  In  some  buildings  we  find  all  the  heating  done 
by  steam  coils,  which  are  placed  in  the  rooms  to  be  heated.  These  coils,  therefore,  act  simply  as  stoves,  and 
do  not  effect  any  change  of  atmosphere  in  the  rooms.  In  modern  buildings,  however,  the  greater  amount  of 
heating  is  placed  in  the  basement,  and  air  from  the  outside  passes  over  the  steam  pipes  and  enters  the  rooms 
from  registers,  the  same  as  in  hot-air  heating.  With  this  appliance,  of  course  the  steam  heater  acts  the  same  as 
a hot  air  furnace  in  supplying  the  warm  air,  and  also,  like  the  air  furnace,  has  the  defect  of  being  shut  off  from 
the  room  by  the  closing  of  the  register  when  the  room  becomes  overheated.  It  is  seen  from  this,  that  whatever 
system  of  heating  may  be  adopted,  unless  there  is  an  adequate  provision  for  the  regulation  of  such  heating  de- 
vice, there  will  be  a deficiency  of  ventilation  in  proportion  as  there  is  a surplus  of  heat.  With  the  variable  cli- 
mate we  have  in  the  United  States,  all  heating  devices  must  have  power  enough  to  keep  the  rooms  at  the  desired 
temperature  during  the  coldest  days  ; but  such  days  are  comparatively  rare,  and  therefore  during  the  remainder 
of  the  time  the  heating  apparatus  has  a capacity  too  great  for  its  use,  and  with  the  utmost  care  will  overheat  the 
rooms.  It  may  be  said  that  the  school-rooms  of  the  United  States  are  overheated  nine-tenths  of  the  time.  The 
inventor  of  this  apparatus,  having  from  experience  and  observation  a knowledge  of  these  facts,  undertook,  by 
some  method,  to  automatically  control  the  heating  and  ventilating  devices.  The  result  of  his  experiments  has 
been  the  Johnson  System  of  Temperature  Regulation, which  is  adapted  to  automatically  control  the  heating  and 
ventilating  of  all  school-rooms  of  whatever  size,  and  to  perfectly  manage,  without  intervention  of  teachers  or 
janitor,  the  heating  device  used  in  the  building,  whether  such  device  be  hot-air  furnace  or  steam  boiler. 

HEAT  CONTROLLING  APPARATUS. 

Attempts  have  been  made  for  upwards  of  thirty  years  to  regulate  heating  apparatus,  but  in  all  such  devices 
as  have  been  heretofore  used  there  has  been  a lack  of  power,  or  the  power  has  been  improperly  applied,  or  the 
device  was  not  adapted  to  all  conditions.  Most  apparatuses  which  have  been  made  have  used  electricity  di- 
rectly to  open  or  close  the  valves,  or  have  used  electricity  to  control  clock  work  which  opens  and  closes  the 
valves  by  means  of  a spring  or  weight.  In  this  method  of  operating  valves,  it  is  evident  that  the  battery  power 
used  needs  be  so  great  in  operating  valves  of  any  practical  size  that  the  apparatus  will  be  both  cumbersome 
and  expensive.  Where  clock  work  has  been  used,  difficulty  arises  from  lack  of  power,  and  in  order  to  get  suf- 
ficient power,  the  apparatus  would  need  to  be  very  large  and  expensive,  and  beside  would  need  close  attention 
to  keep  the  clock  work  wound  up.  It  also  happens  that  the  valves  must  necessarily  be  in  inaccessible  places, 
so  that  any  form  of  clock  work  would  be  hard  to  get  at  to  wind  it.  This  new  invention,  however,  avoids  all 
these  difficulties  by  doing  away  with  the  positive  mechanical  motors,  or  by  valves  to  be  operated  by  electricity 
alone,  and  employs  a form  of  power  much  more  adaptable  to  all  cases,  a mechanism  which  requires  but  little 
space,  and  has  a power  as  great  as  may  be  needed  in  any  particular  case.  The  essential  elements  of  force  in 
the  Johnson  Heat  Regulating  Apparatus  are  electricity  and  fluid  pressure.  Electricity  acts  to  control  the  fluid 
pressure,  and  fluid  pressure  acts  directly  to  operate  the  valves.  Any  one  with  any  reading  upon  the  subject 
whatever  knows  that  fluid  pressure  varies  in  power  in  proportion  of  the  area  of  the  surface  to  which  the  pres- 
sure is  applied.  Thus,  if  there  is  an  area  of  one  square  inch  upon  which  the  force  of  the  fluid  pressure  is  ap- 
plied with  a power  of  ten  pounds,  if  we  apply  the  same  fluid  pressure  to  an  area  of  ten  square  inches,  we  will 
get  a power  of  one  hundred  pounds,  and  as  the  area  to  which  we  apply  the  fluid  pressure  may  be  increased  to 
a large  extent,  it  is  evident  that  with  a fluid  pressure  of  only  a low  power  per  square  inch  we  can  get  an  enor- 
mous power  to  move  such  mechanism  as  we  desire  to  use  in  operating  the  valves.  In  this  device  an  air  pres- 
sure of  ten  pounds  per  square  inch  is  all  that  is  ever  used.  It  will  be  seen  that  with  an  area  of  seventy-eight 
square  inches  (that  is,  the  area  of  a circle  ten  inches  in  diameter),  we  get  a total  pressure  of  seven  hundred  and 
eighty  pounds , which  is  sufficient  to  move  any  valve  ordinarily  used  in  heating.  We  will  not  at  present  fully 

2 


describe  this  apparatus,  but  we  do  so  farther  along.  It  will  probably  occur  to  most  people  reading  this  that  the 
apparatus  is  complicated  and  would  take  up  much  room,  etc. ; but  such  is  not  the  case.  It  is  unobtrusive,  and 
a person  visiting  the  school- room  where  it  is  applied  would  not  notice  that  there  was  anything  different  in  the 
room  than  usual. 

HOW  APPLIED  TO  SCHOOL  ROOMS. 


Fig.  i shows  a part  of  school-room  in  which  the  apparatus  is  applied.  Upon  the  wall,  or  some  support 
in  the  room,  is  a thermostat  A,  which  is  connected  electrically  with  the  apparatus  which  warms  the  room.  As 
usual  in  heating,  the  heat  may  all  pass  through  a register  into  the  room,  or  it  may  pass  partly  through  a regis- 
ter and  partly  through  steam  coils.  The  only  thing  which  appears  in  the  room  aside  from  the  thermometer  are 
the  valves  upon  the  steam  coils,  (if  there  are  any  in  the  room) ; otherwise  the  thermometer,  or  thermostat,  as  it  is 
more  properly  called,  is  the  only  part  of  the  device  which  is  in  the  room.  By  a screw  placed  upon  the  thermos- 
tat it  may  be  adjusted  to  any  degree  of  temperature  which  is  desired.  Thermostats  are  usually  set  at  70  degrees 
Fahrenheit,  and  for  school-rooms  it  is  thought  that  no  higher  degree  of  heat  should  be  used,  whatever  the 
notions  of  the  teachers  may  be  in  that  particular.  From  the  the  thermometer  some  electric  wires,  which  are 
concealed  behind  the  woodwork  or  plaster,  go  to  the  basement,  where  the  rest  of  the  apparatus  is  situated,  as 
is  shown  in  fig.  2. 

These  figures  of  course  do  not  represent  the  apparatus  as  actually  located  in  every  building,  but  are 
placed  in  the  cut  so  as  to  give  the  best  idea  of  their  relations  to  one  another.  The  wires  from  the  thermostat  A, 
in  fig.  1,  pass  to  a small  electrically  actuated  air  valve  B,  and  also  to  the  battery  C,  which  is  placed  in  the  base- 


3 


Fig.  2. 


merit.  This  battery  is  of  the  same  style  as  is  used  with  telephones,  and  requires  no  attention  from  the  occu- 
pants of  the  building  oftener  than  once  in  a year  or  two.  A pipe  D leads  from  this  small  electric  air  valve  to 
the  cylinder  E,  containing  compressed  air;  and  from  the  valve  B another  pipe  F leads  to  the  register  or  valve 
which  is  to  be  operated  by  the  compressed  air ; the  valve,  or  the  register  F,  as  the  case  may  be,  has  an  expan- 
sion chamber  H attached  to  it,  which,  when  inflated  by  the  compressed  air,  pushes  upon  the  valve  and  shuts  it) 
and  which,  when  the  compressed  air  has  escaped,  allows  the  register  or  valve  to  open  again  by  a spring.  The 
thermostat  acts  in  this  way:  When  the  room  is  as  warm  as  desired,  the  thermostat  closes  the  electric  cir- 
cuit and  thus  operates  the  little  valve  B,  and  allows  the  compressed  air  to  pass  from  the  cylinder  E to  the  expan- 
sible chamber  H,  which  operates  the  damper  G and  closes  it,  thus  shutting  off  the  heat.  When  the  heat  is  shut 
off,  of  course  the  room  begins  to  cool,  but  when  it  has  cooled  about  one  or  two  degrees,  the  thermostat  makes  an 
electric  circuit,  which  turns  the  little  valve  B in  the  opposite  direction,  and  shuts  off  the  supply  of  compressed 
air,  and  allows  the  air  which  was  in  the  expansible  chamber  H to  escape  into  the  open  air,  thus  allowing  the 
register  or  valve  to  open.  The  room  will  begin  to  get  warm  again,  but  cannot  go  beyond  the  point  at  which  it 
was  stopped  the  previous  time,  as  at  the  same  point  the  register  or  valve  will  be  shut  again.  Thus  the  valves 
will  be  open  and  shut  alternately  in  short  periods  of  time,  keeping  the  temperature  of  the  room  constantly  at 
the  same  point  so  long  as  the  supply  of  heat  is  maintained  by  the  proper  amount  of  fire. 

The  compressed  air  in  the  cylinder  E is  furnished  by  an  automatic  air  compressor  I,  which  is  operated 
by  the  water  pressure  in  the  building.  By  this  method  of  compressing  air  there  is  no  attention  to  be  paid  to  the 
compressing  of  the  air,  for  the  pump  automatically  maintains  the  pressure  of  ten  pounds  per  square  inch,  or 
such  other  pressure  as  is  desired.  In  school  buildings  where  there  is  no  water  pressure,  we  supply  a hand 
pump  for  compressing  the  air,  the  work  being  done  by  the  janitor  two  or  three  times  a day,  as  it  is  needed,  re- 
quiring two  or  three  minutes  of  his  time  at  each  compression.  The  greatest  amount  of  time  required  to  com- 
press the  air  is  not  greater  than  ten  or  fifteen  minutes  per  day.  So  it  is  seen  that  where  there  is  no  water  pres- 
sure to  compress  the  air,  that  the  compression  of  it  by  hand  is  a very  simple  matter. 

4 


Having  described  the  apparatus  in  general,  we  will  proceed  to  show  different  methods  of  attachment  to 
the  heating  of  the  building. 

In  Fig.  2 is  shown  a section  of  the  hot-air  furnace  to  which  our  apparatus  is  applied  to  regulate  the  tem- 
perature and  ventilation  of  a building.  The  section  given  shows  a furnace  manufactured  by  the  Ruttan  Manu- 
facturing Company  of  Chicago,  which  is  used  largely,  and  to  which  we  have  made  the  attachment  of  our  heat 
regulating  apparatus  in  many  buildings. 

This  furnace  is  designed  to  furnish  a large  amount  of  pure  warm  air  to  each  room,  the  furnace  and  the 
flues  having  a capacity  to  provide  2,000  cubic  feet  of  air  per  hour  for  each  pupil.  In  showing  this  furnace,  we 
will  have  an  opportunity  of  illustrating  how  our  apparatus  is  applied  to  a building  where  the  heating  is  all  indi- 
rect ; that  is,  by  means  of  air  heated  in  the  basement,  and  which  arises  through  the  flues  into  each  room.  Where 
steam  heating  is  used  the  device  is  somewhat  similar,  but  does  not  illustrate  the  apparatus  as  well  as  this  one, 
and  unless  a forced  supply  of  air  is  passed  through  the  coils  by  means  of  a fan,  there  is  usually  less  perfect 
ventilation  in  the  room. 

The  valve  G is  placed  in  a flue  in  such  a way  that  when  it  is  in  the  position  shown  in  the  cut,  it  allows 
the  warm  air  from  the  pipe  J to  pass  freely  into  the  room.  When,  however,  the  damper  G is  raised  by  the  com- 
pressed air  to  a vertical  position  it  shuts  off  the  hot  air,  and  allows  the  cool  air  which  comes  in  through  the  pipe 
K to  ascend  freely  into  the  room. 

It  will  be  seen  from  the  above  description  that,  while  the  thermostat  has  a positive  control  of  the  heating 
of  the  room,  it  does  not  retard  the  ventilation,  as  the  room  is  never  shut  off  from  the  supply  of  air,  warm  or 
cool,  eitlier  one  or  the  other.  Our  apparatus  has  been  used  with  this  attachment  so  far  in  several  buildings,  and 
with  most  excellent  satisfaction.  Besides  operating  the  valves  which  control  the  heating  of  the  room,  we  also 
make  an  attachment  to  the  drafts  of  the  furnace  itself,  so  that  the  fires  will  be  controlled  in  proportion  as  heat 
is  needed.  It  is  evident  that  where  the  attachment  is  made  only  to  the  dampers,  or  valves  which  control  the 
heating  of  each  separate  room,  that  although  the  rooms  cannot  be  overheated,  yet  the  fires  will  not  be  checked 
unless  attended  to  by  the  engineer  or  janitor.  It  is  therefore  highly  important,  both  as  a matter  of  economy 
and  safety,  to  control  the  fires  as  well  as  the  heating  of  the  rooms.  Where  applied  to  the  drafts  of  the  furnace, 
a diaphragm  mechanism  is  shown  in 

HOW  FUEL  IS  SAVED. 

F'g-  3.  vvhich  is  easy  to  operate  so  that  the  drafts  of  the  furnace  will 
be  either  checked  or  opened,  as  there  is  necessity  for  heat  in  the  rooms. 
We  do  not  deem  it  important  or  expedient  to  show  the  whole  of  the  ap- 
paratus here,  but  it  is  sufficient  to  say  that  it  operates  in  this  wise  : Let 
us  suppose  that  four  rooms  are  heated  by  the  same  furnace;  the  draft  reg- 
ulating apparatus  is  so  attached  that  when  all  four  rooms  are  sufficiently 
warm,  and  the  heat  shut  off,  that  the  diaphragm  mechanism  will  operate 
the  furnace  so  as  to  check  the  fire.  This  prevents  the  furnace  overheating, 
and  also  the  waste  of  fuel  when  it  is  not  needed.  It  is  very  easy  to  be 
seen  that  during  mild  weather  the  heat  will  be  shut  off  from  the  rooms 
a great  proportion  of  the  time,  and  consequently  the  drafts  of  the  furnace 
will  be  checked  a correspondingly  large  part  of  the  time,  and  thus  the 
furnace  will  keep  up  a very  slow  and  mild  heat. 

This  draft  mechanism  is  also  arranged  so  that  when  eitlier  one  of  the  thermostats  opens  the  register  or 
valve  for  that  room,  that  the  drafts  of  the  furnace  will  also  open  and  start  the  fire.  This  prevents  any  one  room 
getting  too  cool  when  others  may  be  warm  enough,  and  also  prevents  the  fire  getting  so  low  as  not  to  start 
readily  when  heat  is  needed.  When,  however,  all  the  valves  are  closed  because  the  rooms  are  warm,  the 

5 


r & 


drafts  of  the  furnace  will  also  close,  and  thus  check  the  fire.  This  makes  the  furnace  perfectly  automatic  in  re- 
gard to  the  amount  of  heat  furnished,  and  that  not  a pound  of  fuel  can  be  wasted,  since  the  furnace  drafts  respond 
perfectly  to  the  need  of  heat. 

We  wish  to  call  particular  attention  to  the  effect  that  our  apparatus  has  on  the  distribution  of  the  heat 
throughout  the  building.  Any  one  who  has  had  any  experience  either  in  heating  buildings, 
or  in  using  buildings  which  are  heated  by  warm  air,  knows  that  it  is  utterly  impossible  to  so 
arrange  the  heating  apparatus  or  the  size  of  the  flues  as  to  give  at  all  times  and  under  all 
circumstances  the  proportional  amount  of  heat  to  each  room.  As  an  illustration,  let  us  take 
four  rooms  of  a school  building,  and  let  these  rooms  represent  one  floor  of  the  building,  one 
room  being  in  each  corner.  Now,  it  is  evident  that  when  the  wind  is  in  the  northeast  the 
room  in  that  corner  of  the  building  will  not  be  heated  as  well  as  the  one  in  the  southwest 
corner,  because  the  tendency  of  the  atmosphere  outside  the  building  is  to  throw  the  air  in  the 
building  toward  the  direction  in  which  the  wind  is  going.  In  this  case, the  northeast  corner  room 
will  either  not  be  heated  enough,  or  the  southwest  corner  room  will  be  heated  too  much.  With 
a constant  variation  of  wind  from  day  to  day,  there  is  a constant  and  corresponding  deflection 
of  the  air  circuits  within  the  building  itself,  so  that  it  becomes  utterly  impossible  to  equally  dis- 
tribute the  heat.  The  Johnson  Heat  Apparatus  entirely  remedies  this  defect,  and  it  is  one 
of  its  most  important  and  greatest  advantages.  To  show  how  this  is  so  we  will  illustrate  it 
by  four  rooms.  As  said  above,  if  the  wind  is  in  the  northeast,  the  southwest  room  will  get  warm 
first ; but  as  the  thermostat  shuts  the  heat  off  from  that  room  at  the  proper  degree  of  tempera- 
ture, all  the  air  from  the  furnace  will  be  forced  into  the  other  three  rooms.  This  being:  so, 
the  southeast  and  northwest  corner  rooms  will  next  become  sufficiently  heated  ; and  in  like  man- 
ner the  thermostats  in  these  two  rooms  will  shut  off  the  heat  from  them,  as  in  the  case  of  the 
southwest  corner  room.  Now,  since  three  of  the  rooms  are  shut  off  from  the  furnace,  all  the  air 
from  the  furnace  will  be  forced  to  enter  the  northeast  room  against  its  natural  direction.  This 
will  bring  the  last  room  to  a proper  degree  of  heat,  and  during  the  day  it  is  easily  understood 
that  for  a larger  portion  of  the  time  the  other  rooms  will  be  shut  off,  and  the  heat  for  the  greater 
portion  of  the  time  be  thrown  into  this  one  room.  This  gives  an  absolutely  equal  distribution 
of  the  heat  of  itself,  which  can  be  attained  in  no  other  way  and  by  no  other  means. 

PARTS  OF  THE  APPARATUS. 

Fig.  4 is  a view  of  the  thermostat,  which  is  placed  on  the  wall  of  the  room.  To  a casual 
observer  it  is  a thermometer  only,  having  a fine  mercury  column  and  plain  figures  upon  its 
ace.  We  would  say,  however,  that  the  thermometer  nor  the  mercury  have  anything  to  do  with  the  device.  The 
electric  circuits  are  made  by  means  of  expansion  and  contraction  of  a bar  which  is  fastened  near  the  top  behind 
the  thermometer,  and  whose  lower  end,  by  means  of  a tongue  (seen  in  the  cut  near  the  bottom),  is  free  to  move 
from  right  to  left  and  make  electric  circuits,  first  with  one  and  then  the  other  point.  The  wires  from  the  ther- 
mostat lead  from  the  three  binding  posts,  seen  at  the  bottom,  to  the  small  electro-pneumatic  valve  which  has 
previously  been  spoken  of,  and  which  is  usually  located  in  the  basement.  The  working  parts  of  the  thermostat 
are  very  durable,  and  cannot  get  out  of  order  unless  very  rudely  tampered  with.  In  some  cases  we  cover  them 
up  with  guards,  to  prevent  children  and  others  from  meddling  with  them. 

When  it  is  desired  to  adjust  the  thermostat  to  any  desired  temperature,  it  is  done  by  turning  the  screw  A,  on 
the  side  of  the  thermostat,  as  shown  in  the  cut.  This,  however,  does  not  need  to  be  done  excepting  at  long 
periods  of  time,  and  the  most  that  we  ask  for  the  thermostat,  as  with  most  other  parts  of  the  apparatus,  is  that 

6 


40] 


30  I 


20  I 


HO 


Fig.  4. 


it  be  let  alone.  In  the  drawing  the  thermometer  is  seen  to  be  at  70,  and  that  is  the  point  at  which  the  ther- 
mostat should  be  set  in  the  school-room  ; never  higher  than  that,  at  least. 


Fig.  5 shows  the  electro- 
pneumatic valve  which  is  ope- 
rated by  the  thermostat.  This  is 
placed  usually  in  the  basement. 
All  the  working  parts  of  it  are 
concealed  within  the  casing, 
and  are  very  durable,  and  in 
such  a position  that  they  can 
never  be  injured  by  either  chil 
dren  or  dust.  The  four  spools 
shown  in  the  drawing  are 
wound  with  electric  wire  that 
produces  the  magnetism  to  op- 
erate the  valve.  The  electric 
wires  are  attached  to  the  bind- 


ing posts  on  the  base,  one  of 
which  posts  only  is  seen  in  the 
cut.  The  battery  needs  no  par- 
ticular description,  as  it  is  one 
of  the  ordinary  sorts  used  with 
the  telephone  and  to  ring  elec- 
tric bells.  There  are  probably 
not  less  than  1 ,000,000  of  these 
in  use  in  the  United  States  at 
the  present  time.  They  re- 
quire very  little  attention.  We 
place  the  battery  in  the  base- 
ment, as  shown  in  fig.  2,  and 
generally  use  about  four  cells. 


F'g-  5- 


Fig.  6. 


Fig.  6 shows  an  automatic  air  compressor.  This 
compressor  is  applied  to  the  water  supply  of  the  build- 
ing, and  keeps  the  air  cylinder  full  of  compressed 
air  without  any  attention  from  any  one.  It  will  run 
for  months,  night  and  day,  without  looking  after,  ex- 
cept to  put  a little  oil  upon  it  once  in  a while. 

We  would  say  that  the  air  compressor  does  not 
run  continuously  and  thereby  waste  water,  but  only 
moves  as  the  supply  of  air  is  exhausted.  If  no  air  is 
used  the  air  compressor  does  not  work,  but  as  soon 
as  any  of  the  air  is  used,  it  works  just  long  enough 
to  make  up  the  loss.  Thus  very  little  water  is  used 
to  keep  a pressure  of  air  ; so  little  in  fact  that  the 
waterworks  departments  seldom  make  any  charge 
for  the  water  used.  When  there  is  no  water  system 
used  in  the  building  we  use  a hand  pump. 

Where  there  are  a great  many  rooms  to  be  con- 
trolled, and  there  is  no  water  system,  we  use  a larger 
hand  pump,  which  is  turned  by  a crank. 

The  valve  operating  mechanism  differs  very  much, 
depending  upon  the  size.  On  steam  pipes  we  use  a 
valve  which  is  similar  in  most  respects  to  an  ordinary 
valve,  but  has  on  it  a chamber  through  which  the 
compressed  air  pushes  the  valve  shut. 


T. 


Fig.  7.  Fig- 

Fig.  7 shows  the  outside  of  one  of  these  valves,  which  is  adapted  to  be  put  upon  a steam  radiator. 
Fig.  8 is  a sectional  view  of  this  same  valve,  showing  how  it  operates. 


Fig.  1 1 is  a butterfly  damper  put  in  a hot  air  flue,  and  may  be  made  of  any  size  required. 

Fig.  12  is  a square  valve  to  be  put  in  the  angle  of  a square  pipe  or  flue  to  shut  off  the  warm  air  and  al- 
low cool  air  to  enter  the  room,  and  when  the  room  cools  a little  to  reverse  and  allow  the  hot  air  to  again  enter. 


Fig.  9. 


Fig.  9 shows  a radiator  with  electric  valves  attached.  These  valves  shown  in  fig.  10  are  at  either  end  of 
the  steam  coil. 


Fig.  10  shows  a globe  valve,  which 
is  similar  in  its  mechanism,  but  is  made 
to  be  placed  on  a straight  pipe  instead 
of  an  angle.  These  valves  are  shown 
in  fig.  9,  at  either  end  of  the  steam 
coil.  It  will  be  seen  that  they  occupy 
but  a small  space,  and  are  not  large 
and  ungainly.  The  valve  shuts  with 
a piston  motion,  and  is  held  to  its  seat 
with  a cushion  of  air  having  a pressure 
of  from  50  to  300  pounds,  according 
as  the  case  demands.  For  this  reason 
the  electric  valve  never  grinds  or  de- 
stroys its  seat.  It  makes  no  difference 
how  much  the  stem  or  other  parts  may 
shrink  in  cooling,  the  valve  is  just  as 
firmly  seated,  for  the  elastic  pressure 
will  take  every  advantage  of  the  shrink- 


Fig.  10. 


age  to  seat  the  valve  closer.  When 
the  electric  valves  are  applied  to  a sys- 
tem of  heating,  they  are  always  all 
open  when  the  steam  is  down.  There 
is  no  need  of  going  about  a building 
to  see  to  .them,  for  the  pipes  are  all 
free,  and  no  water  can  collect  to  freeze. 
When  the  fires  are  started  the  steam 
passes  freely  to  all  parts  of  the  sys- 
tem. Not  only  does  the  valve  shut 
steam  off  from  rooms  that  are  warm 
enough,  but  since  it  shuts  off  the  ra- 
diating surface  that  is  not  needed,  the 
pressure  rises  accordingly,  and  distri- 
butes the  heat  to  rooms  which  are  not 
yet  warm  enough,  thus  acting  as  an 
equalizer.  With  the  electric  valve  it 
is  possible  to  keep  up  a sufficient  pres- 


sure to  warm  the  coldest  room  in  the  building  without  the  least  overheating  any  other  room.  For  this  reason 
alone  the  electric  valve  is  worth  ten  times  its  cost.  Figure  7 shows  the  diaphragm  applied  to  an  angle  valve  ; 
but  we  make  all  other  forms  of  valves,  such  as  globe  (fig.  10),  gate,  butterfly,  etc.,  and  each  works  equally  well. 
For  indirect  radiation  we  apply  the  valves  directly  to  coils  which  heat  the  air,  to  the  cold  air  box  which  supplies 
the  air,  or  to  the  register. 


9 


FACTS  AND  OPINIONS. 

MILWAUKEE  SCHOOLS. 

Recent  investigations  show  a saving  of  15  per  cent,  in  fuel  used  in  the  public  schools  of  Milwaukee  dur- 
ing the  winter  of  1885-6,  where  our  Heat  Regulating  Apparatus  has  been  applied.  From  official  records  in  the 
office  of  the  Secretary  of  the  School  Board,  complete  with  reports  from  Principals  named  below,  the  following 
data  have  been  obtained  : 

COAL  USED  DURING  THE  WINTER  OF  1885-86. 


Name  of  School. 

Cubic  Contents. 

Tons  of 
Coal  Used. 

Space  per  Ton. 

Average 
Space  per  Ton. 

Remarks. 

1st  District,  - 

258,000  Cubic  feet. 

132 

1954  | 

Without 

1 2th  District, 

300,000 

153 

i960  j 

1957 

our 

Apparatus. 

9th  District,  - 

372,000  Cubic  feet. 

167 

2227  'j 

With 

10th  District, 

346,000  “ 

152 

2261  J 

2247 

our 

Apparatus. 

This  shows  a saving  of  14.6  per  cent,  of  fuel  in  the  9th  and  10th  District  Schools.  Our  Apparatus  was 
placed  on  the  heating  for  school  rooms  only;  had  it  been  placed  on  heaters  in  cloak  rooms  and  corridors  the 
saving  would  have  been  much  more. 

The  style  of  heating  in  these  four  buildings  is  the  same  ; the  boilers  are  all  of  the  same  pattern,  and  the 
radiation  and  its  distribution  being  alike  in  every  particular. 

The  above  facts,  in  connection  with  the  uniform,  healthful  temperature  secured  by  our  Apparatus,  have 
led  to  its  adoption  by  the  Board  of  Public  Works  for  all  school  buildings,  new  and  old,  for  which  heating  appa- 
ratus has  to  be  supplied. 

We  are  pleased  to  furnish  the  following  communication  from  the  Board  of  Public  Works  of  the  city  of 
Milwaukee,  and  the  Superintendent  of  Schools  of  that  city  : 

Office  of  the  Board  of  Public  Works,  ) 
Milwaukee,  August  10th,  1886.  J 

Gentlemen  : 

We  take  pleasure  in  saying  that  your  Heat  Regulating  Apparatus,  placed  in  four  of  our  public  school 
buildings,  has  given  entire  satisfaction,  regulating  the  temperature  as  guaranteed,  thus  saving  fuel  and  attention. 

As  applied  to  our  schools,  all  direct  radiation  for  one  room  being  placed  in  one  coil  (instead  of  six  or 
eight,  as  usual  where  heat  has  to  be  regulated  in  the  ordinary  way),  we  have  found  that  the  original  cost  of  the 
heating  plant  has  been  increased  but  very  little,  and  we  heartily  recommend  its  use  in  all  school  buildings  where 
large  numbers  of  children  are  necessarily  confined  the  greater  part  of  school  hours. 

C.  P.  FOOTE, 

W.  P.  O’CONNOR, 

GEO.  P.  TRAEUMER, 

Commissioners  of  Public  Works. 

10 


Oefice  of  the  School  Board, 

Cor.  Seventh  and  Prairie  Sts., 
Milwaukee,  August  12,  1886. 

Dear  Sirs: 

It  affords  me  great  satisfaction  to  state,  in  regard  to  the  efficiency  of  your  Heat  Regulating  Apparatus, 
that  our  experience  with  the  improvements  supplied  last  winter  to  the  8th,  9th,  10th  and  12th  district  primary 
schools  has  thoroughly  convinced  us  of  the  truth  of  the  following  facts: 

First.  Your  apparatus  is  automatic,  and  maintains  an  equable  temperature,  never  higher  than  that  re- 
quired, and  only  lower  as  the  fire  burns  out  or  down.  This  seems  a very  simple  result  in  the  problem  of  heat- 
ing, but  not  till  we  had  made  a practical  test  of  this  modern  device  did  we  realize  the  great  luxury  to  be  enjoyed, 
and  the  great  increase  of  comfort  which  is  the  accompaniment  of  this  one  simple  fact. 

Second.  VVe  have  pretty  good  evidence  to  show  that  your  apparatus  saved  a considerable  part  of  its  cost 
in  the  saving  it  effected  in  fuel.  Similar  schools,  two  containing  the  Regulator  and  two  not,  have  been  visited 
and  account  of  coal  consumed  has  been  compared.  The  difference  is  so  marked  that  we  can  hardly  find  any 
other  explanation  than  that  the  Electric  Service  has  effected  a saving  of  about  15  per  cent. 

Third.  We  find  a great  advantage  and  merit  in  your  Apparatus  over  the  clumsy  and  less  modern  con- 
trivance, called  the  janitor.  Always  prompt  and  true  and  sensible,  it  quite  relieves  the  school  of  that  average 
bustling  appendage  during  school  hours.  In  short,  I cannot  recommend  your  contrivance  too  highly.  It  is 
the  one  essential  to  thoroughly  reliable  heating  apparatus.  Without  it  the  apparatus  is  not  modern,  is  deficient 
in  the  most  important  improvement  that  has  ever  been  added  to  heating  devices  in  one  invention. 

Yours  truly, 


W.  E.  ANDERSON, 

Supt.  of  Public  Schools. 


High  School,  Milwaukee,  Wis.,  1 
April  29,  1887.  J 

Gentlemen:  I am  much  pleased  with  the  operation  of  your  heat  regulating  apparatus  which  is  applied 
throughout  this  building.  The  temperature  of  every  room,  hall  and  corridor  is  regulated  thereby  to  a definite 
standard,  and  not  by  the  personal  peculiarity  of  the  teachers,  some  of  whom  would  otherwise  be  satisfied  with 
a temperature  much  lower  or  much  higher  than  what  is  normal  and  healthful  for  our  pupils.  This  I consider 
a great  gain.  The  saving  in  attention  to  the  heating  apparatus,  and  from  the  annoyance  from  over-heating 
and  under-heating,  amply  repay  the  cost  of  your  apparatus. 

gp:o.  w.  peck  ham, 

Principal. 


From  Principal  Ninth  Ward  Public  School. 

Milwaukee,  January  19,  1886. 

Gentlemen:  Your  Heat  Regulating  Apparatus  has  proved  to  be  an  entire  success  in  our  school  build- 
ing. It  works  well,  easily,  without  any  trouble,  and  has  not  failed  yet  since  its  introduction.  We  are  highly 
pleased  with  it,  and  I recommend  it  in  good  faith.  I would  like  to  say  more  in  favor  of  this  Apparatus,  but  I 
am  confined  to  my  bed.  Yours  truly, 

LOUIS  HILLMANTEL. 


11 


From  Principal  Tenth  District  School,  Milwaukee. 

Gentlemen:  It  is  with  pleasure  that  I certify  to  the  merits  and  effectiveness  of  the  “ Electric  Service” 
as  applied  to  regulating  the  temperature  of  our  school  rooms.  I never  imagined  that  the  Apparatus  could  be 
so  perfect,  or  that  it  would  so  fully  meet  the  requirements;  but  after  four  months  of  trial,  with  the  thermometer 
varying  from  40°  above  to  20°  below,  our  20  cl  iss  rooms,  2 offices,  large  exhibition  hall,  22  teachers,  and  1,200 
pupils  were  all  comfortably  warmed — the  first  time  since  I have  been  teaching.  The  even  temperature  has  been 
conducive  to  the  health  of  pupils  and  teachers. 

I therefore  pronounce  the  Heat  Regulating  Apparatus  an  unqualified  success,  and  take  pleasure  in  recom- 
mending it  to  all  principals  and  school  officers  for  introduction  in  the  various  school  houses.  I trust  that  the 
public  in  general  will  not  be  slow  in  making  use  of  this  reliable  health-giving  and  fuel-saving  Heat  Regulating 
Apparatus.  Very  truly  yours,  JOHN  A.  DIEDRICHSEN, 

Principal  Tenth  District  School,  Milwaukee,  VVis. 

Milwaukee,  April  26th,  1887. 

Gentlemen:  The  Johnson  Heat  Regulating  Apparatus  is  in  use  in  six  school  rooms  and  two  offices 
in  our  school.  It  has  proved  itself  reliable  and  satisfactory  as  a means  of  regulating  the  amount  of  neat  admit- 
ted to  the  rooms.  While  there  is  yet  something  to  be  done  to  control  the  amount  of  cold  air  directly  admitted 
to  the  rooms  where  the  apparatus  is  in  use,  in  order  to  secure  the  full  comfort  of  teachers  and  pupils,  I am  sat 
isfied  that  as  far  as  the  responsibility  of  the  Heat  Regulating  Apparatus  is  concerned,  there  is  no  fault  to  find. 
The  ventilation  of  the  rooms  where  the  Heat  Regulating  Apparatus  is  in  use  seems  to  be  perfect,  while  in  the 
other  nine  rooms  of  the  building  it  is  far  from  perfect. 

I believe  the  Johnson  Apparatus  is  conducive  to  health,  mental  vigor,  and  sweet  good  nature. 

Very  respectfully,  LEWIS  FUNK, 

Principal  Seventh  District  School. 

Milwaukee,  Wis.,  April  26,  1887. 

Gentlemen:  Your  Heat  Regulating  Apparatus  has  been  in  use  in  this  building  for  one  year,  so  I have 
had  ample  time  to  test  it  in  all  kinds  of  weather.  I am  pleased  to  say  that  it  never  allows  the  rooms  to  be 
overheated.  It  takes  care  of  the  valves  on  the  steam  heating  apparatus,  so  that  our  teachers  never  have  to  give 
attention  to  the  matter  of  regulation  of  heat.  So  far  it  does  this  work  properly. 

KATE  G.  McCABE, 

Principal  Twelfth  District  Primary  School. 

MENOMONEE  SCHOOLS. 

Menomonie,  Wis.,  March  3,  1887. 

Gentlemen:  We  have  nothing  but  words  of  approval  for  the  Apparatus.  It  does  its  work  perfectly, 
and  without  any  fuss  or  trouble.  It  has  not  been  touched  nor  interfered  with  in  any  manner  since  it  was  placed 
in  operation.  Since  it  has  been  in,  we  have  not  had  to  open  a single  window  in  any  one  of  the  ten  large  rooms 
to  which  it  is  attached,  a ‘thing  which  has  not  happened,  prior  to  this,  during  my  eleven  years  work  here. 
While  we  in  this  building  are  sitting  in  comfort  with  closed  windows,  those  in  the  other  buildings  are  compelled, 
several  times  daily,  to  throw  open  the  windows,  and  suffer  all  the  inconveniences  of  such  a system  of  reducing 
the  temperature  of  an  overheated  room. 

Our  janitor  claims,  and  zviih  the  proojs  before  lam,  that  he  does  not  use  quite  two  thirds  the  fuel  formerly 
used.  Very  truly  yours,  JOHN  G.  INGALLS, 

Principal  City  Schools,  Menomonie,  Wis. 

12 


HYDE  PARK  SCHOOLS. 

Hyde  Park,  111.,  March  5,  1887. 

Gentlemen  : It  gives  me  pleasure  to  comply  with  your  request  for  a statement  of  our  experience  with 
your  Automatic  Heat  Regulator.  We  have  thoroughly  tested  the  Apparatus  in  the  new  High  School  for  this 
district  for  more  than  six  months,  with  the  following  result: 

1st.  The  temperature  is  practically  invariable;  e.  g.,  in  the  ten  rooms  during  one  week  of  the  coldest 
weather,  an  observation  of  the  temperature  was  taken  and  recorded  once  an  hour  for  five  days,  with  a result 
of  variation  of  less  than  three  degrees  in  any  room. 

2d.  A considerable  saving  in  care  to  teachers  constantly  watching  the  temperature. 

3d.  A great  gain  in  the  hygienic  condition  of  the  rooms,  due  to  the  equable  temperature. 

4th.  A large  economy  in  fuel. 

These  facts  are  sufficient  to  satisfy  me  that  the  Automatic  Apparatus  is  most  desirable  in  every  school 
building,  and  to  justify  me  in  recommending  it  to  all  school  officers. 

Yours  very  truly,  W.  H.  RAY, 

Principal. 

Hyde  Park,  111.,  April  12,  1887. 

Gentlemen:  The  Electric  Apparatus  which  you  put  into  our  High  School  building,  for  the  purpose  of 
regulating  the  temperature  in  the  different  rooms,  is  doing  all  that  it  was  expected  to  do. 

After  it  was  once  properly  adjusted,  it  shut  off  the  hot  air  as  soon  as  the  temperature  reached  70  degrees, 
and  immediately  opened  the  valves  and  admitted  the  warm  air  when  the  temperature  went  below  70  degrees. 
It  is  better  than  any  human  agency,  since  it  is  not  negligent  and  does  not  get  tired.  It  requires  little  or  no 
care,  is  quickly  adjusted  to  any  temperature  required,  and  does  not  easily  get  out  of  order. 

Yours  truly,  LESLIE  LEWIS, 

Superintendent  of  Schools. 


JOSHUA  BATES  SCHOOL,  BOSTON. 

From  The  Sanitary  Engineer  of  May  6,  1886,  we  take  pleasure  in  reproducing  the  following  clipping  from 
an  article  descriptive  of  the  Joshua  Bates  School,  Boston.  The  article  has  reference  to  the  architecture,  furnish- 
ing, ventilating  and  heating  of  the  building.  To  indicate  that  the  writer  was  entirely  disinterested  in  regard  to 
his  tests  of  our  Apparatus,  we  would  say  that  who  he  is  we  do  not  know,  and,  moreover,  that  we  did  not  know 
of  the  article  having  appeared  in  The  Sanitary  Engineer  until  some  months  afterward,  when  our  attention  was 
called  to  it  by  some  correspondent.  The  paragraph  in  regard  to  the  heating  is  as  follows.  (The  italics  are  ours) : 

“ The  temperature  of  the  rooms  varied  from  67  to  82  degrees.  In  one  of  the  rooms  a damper  for  allow- 
ing the  fresh  air  to  enter  the  room  without  passing  through  the  radiators  was  placed  in  the  box.  This  damper 
was  regulated  to  open  automatically  when  the  temperature  of  the  room  reaches  68  degrees,  by  an  arrangement 
supplied  by  the  Johnson  Electric  Service  Company.  Another  room  was  provided  with  the  Johnson  Electric 
valves,  which  shut  off  the  steam  when  the  temperature  of  the  room  reaches  68  degrees,  and  lets  it  on  again 
when  the  mercury  falls  below  that  point.  Both  these  valves  and  the  damper  are  worked  by  an  automatic  appa- 
ratus, depending  upon  electricity,  compressed  air,  and  the  principle  of  the  the  thermostat.  The  temperature  in 
these  two  rooms  did  not  exceed  69  degrees.  In  the  other  rooms  the  temperature  varied  from  68  to  82  degrees,  the 
average  of  the  six  rooms  being  74  1-2  degrees.  The  pressure  of  the  steam  in  the  boiler  varied  from  six  to  ten 
pounds.”  ( The  Sanitary  Engineer,  May  6,  1886.) 

14 


FROM  THE  WAUKESHA  SCHOOLS. 

Waukesha,  Wis.,  April  i,  1887. 

Gentlemen:  It  is  always  a pleasure  to  recommend  a good  thing.  Your  apparatus  for  regulating  tem- 
perature has  been  in  use  in  twelve  rooms  of  our  school  building  since  last  September.  To  say  that  we  are 
greatly  pleased  with  it  would  be  a very  mild  statement.  There  are  three  reasons  why  we  would  not  be  without 
it,  any  one  of  which  is  sufficient. 

1st.  Comfort.  Our  rooms  are  just  warm  enough,  never  too  warm;  and  there  are  no  draughts  from 
windows  opened  to  cool  the  room. 

2d.  Convenience.  The  teacher  does  not  have  to  think  of  temperature  from  morning  to  night,  and  can 
give  her  undivided  attention  to  her  work,  without  being  interrupted  every  few  minutes  by  the  room  getting  too 
warm  or  too  cold. 

3d.  Economy.  It  is  costing  us  16^  per  cent,  less  to  heat  the  same  space  in  our  building  this  year  than 
last,  and  it  is  better  done.  This  is  a surprise  to  us  ; for  we  have  thoroughly  ventilated  the  building,  and  from 
the  best  estimate  we  could  make  we  concluded  that  it  would  cost  us  at  least  25  per  cent,  more  to  heat  it  than 
before.  We  attribute  this  largely  to  your  Apparatus. 

It  is  one  of  the  most  valuable  appliances  ever  put  into  a school  building. 

Very  truly  yours,  G.  H.  REED,  Principal. 

Waukesha,  Wis.,  April  2,  1887. 

Gentlemen:  I have  been  on  our  school  board  here  for  the  past  fifteen  years  ; have  studied  the  heating 
and  ventilating  question  earnestly.  Last  year,  in  enlarging  and  greatly  improving  our  old  building,  we  intro- 
duced the  Ruttan  system  of  heating  and  ventilation,  at  the  same  time  introducing  into  12  rooms  your  Appa- 
ratus for  regulating  the  same. 

I will  simply  say,  for  purity  of  atmosphere  in  all  of  the  rooms,  even  temperature  and  economy  of  fuel, 
this  system  strikes  us  as  being  as  near  to  perfection  as  anything  can  be,  which  result  is  largely  due  to  your 
Heat  Regulating  Apparatus.  It  never  tires  nor  stops  its  use.  The  janitor  in  the  basement  is  automatically  ap- 
prised whether  each  room  is  at  the  required  temperature  or  not,  and  can  regulate  his  fires  accordingly.  We 
cheerfully  invite  inspection.  Very  truly  yours,  A.  J.  FRAME, 

Treasurer  School  Board,  President  Waukesha  National  Bank. 


COUNCIL  BLUFFS  SCHOOLS. 

Council  Bluffs,  la.,  January  19,  1887. 

Gentlemen:  We  desire  to  express  to  you  the  unqualified  satisfaction  which  the  Johnson  Heat  Regu- 
lating Apparatus,  placed  by  you  in  our  Pierce  Street  School,  is  giving. 

The  heating  apparatus  in  this  school  in  preceding  years  has  failed  to  heat  the  building  well.  The  changes 
which  you  recommend  in  connection  with  the  Apparatus,  in  combination  with  the  Johnson  System,  has  enabled 
us  to  heat  the  building  completely.  The  temperature  has  been  perfectly  controlled  to  a uniform  standard  in  all 
the  rooms  during  this  severe  winter,  and  a considerable  economy  in  fuel  has  already  been  secured,  as  compared 
with  previous  years.  The  recommendations  which  you  have  given  in  regard  to  other  heating  plants  in  our 
schools  have  proved  valuable  to  our  board,  and  the  good  results  have  been  attained  at  a very  moderate  expendi- 
ture of  money.  In  view  of  these  facts,  we  desire  you  to  submit  proposals  that  shall  cover  the  application  of 
the  Johnson  Heat  Regulating  appliances  to  other  buildings  under  our  charge  that  are  heated  by  steam  or  the 
Ruttan  system.  R.  T.  BRYANT, 

J.  R.  BELL, 

J.  B.  ATKINS,  President  Board, 
is 


■Committee  on  Heating,  etc. 


Council  Bluffs,  la.,  April  6,  1887. 

Gentlemen  : 1 take  pleasure 

in  stating  that  the  Johnson  Heat  Regulating  Apparatus,  in  the  matter  of 

regulating  the  temperature  of  our  school  rooms,  in  connection  with  the  steam  and  hot  air  systems,  works  to 

our  entire  satisfaction.  Respectfully 

yours, 

JAS.  McNAUGHTON, 

Superintendent  of  Schools. 

NEW  YORK  CITY  SCHOOLS. 

Grammar  School  No.  68,  J 

1 16  West  128th  Street,  > 

New  York,  April,  1887.  j 

Gentlemen:  In  accordance  with  a request  from  the  Board  of  Trustees  of  the  Twelfth  Ward,  the  two 

rooms  that  were  the  most  difficult  to  keep  at  an  even  temperature,  and  in  which  the  teachers  and  pupils  suffered 

greatly  from  excessive  heat  during  the  winter,  were  selected  to  test 

your  Heat  Regulating  Apparatus. 

The  usual  range  of  the  thermometer  was  from  74  to  84  degrees.  Since  the  introduction  of  your  Appa- 

ratus  the  temperature  has  varied  so  s 

ightly  from  the  figures  at  which  the  thermostat  was  set  (70  deg.),  that  it 

could  not  be  detected  by  sensation,  but  only  by  closely  watching  the  thermometer,  and  what  you  claimed  for  it 

has  been  accomplished,  and  we  hope 

the  Board  will  see  fit'to  put  it 

in  every  room  in  this  department. 

JULIET  PEARSON,  Principal. 

CARRIE  E.  HIGHET,  Class  Teacher. 
KATE  L.  BOGART,  Class  Teacher. 

THE  JOHNSON  HEAT  REGULATING  APPARATUS 

is  already  in  use,  or  has  been  specified,  for 

the  following  schools,  at  the  date  of  this  writing,  and  others  are  falling  into  line  constantly. 

NEW  YORK. 

MILWAUKEE. 

ST.  PAUL,  MINN. 

Grammar  School  No.  68. 

New  High  School. 

Jefferson  School. 

(Two  Rooms.) 

1st  District  Primary. 

Madison  School. 

BOSTON. 

7th  District  Addition. 

Lincoln  School. 

Joshua  Bates  School. 

8th  District  Branch. 

COUNCIL  BLUFFS. 

(Two  Rooms.) 

9th  District. 

Bloomer  St.  School. 

CHICAGO. 

10th  District. 

Pierce  St.  School. 

P'roebel  School. 

1 1 th  District. 

ROCK  ISLAND. 

Grant  School. 

1 2th  District  Primary. 

High  School. 

HYDE  PARK. 

WOODLAWN,  ILL. 

BELOIT,  WIS. 

High  School. 

High  School. 

Ward  School. 

WAUKESHA,  WIS. 

ELKHORN,  WIS. 

MENOMONIE,  WIS. 

Union  School. 

High  School. 

16 

High  School. 

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